Fibrous insulation material is typically manufactured in common lengths and widths, called insulation batts, to accommodate typical building frame structure dimensions. Fibrous insulation batts are commonly made of mineral fibers, such as glass fibers, and usually have a density within the range of from about 0.2 to about 1.0 pounds per cubic foot (3.2 to 16 kg/m.sup.3). Typical batt sizes are 16 or 24 inches (40.6 cm or 61.0 cm) wide by 8 feet (2.44 m) long. These batts can be packaged in various ways. The batts can be staggered and rolled together along their lengths so that a roll would contain about 10 batts. Alternatively, the batts can be stacked on top of each other, compressed and then packaged in plastic bags. Because of size constraints it is desirable to fold the batts in half along their lengths and stack them together, thereby forming a stack which is about 4 feet (1.22 m) long. The invention as described herein pertains to the packaging of the folded batts.
Presently, the insulation batts are simply folded in half and deposited horizontally in a stacker which collects the folded batts and packages them. The batts can be folded either manually or by a folding machine which uses a ram to push on the center of the batt and insert the batt into a gap between two conveyors to fold the batt, as described in U.S. Pat. No. 4,805,374 to Yawberg. The folded batts are stacked vertically in the stacker until a certain desired number of batts is accumulated. After a sufficient number of batts has been accumulated in the stacker, the accumulated batts are then compressed and packaged into a plastic bag.
One of the problems with a conventional batt folding and packaging system is that the folded batts have a tendency to unfold by themselves unless they are constrained. The folded batts do not stack well because the batts do not stay folded in an even flat shape. Because ale fibrous insulation at the folded end of the batt is under compression, the top section or half of the insulation batt lifts above the bottom section at the unfolded end due to the natural springiness of the insulation. The partially unfolded batt resembles a wedge-shaped figure where the top folded section or half is at an angle to the bottom half. This results in the open end of the folded batt having a greater thickness than the folded end of the batt.
When the wedge-shaped folded batts are stacked on top of each other in the stacker, the accumulation of the increased side thickness causes the stack to lean. This uneven stacking can cause the folded batts to unfold or tip over, thereby jamming the stacker. To prevent batts from unfolding, compressed air is used to force down the top section of the folded batts. The use of the compressed air is only partially effective and has the undesirable qualities of being very noisy, spreading loose insulation fibers and dust into the air, and being very costly.
It would be desirable to have a way of folding lengths of fibrous insulation batts so that they remain folded and are not wedge-shaped when in an unrestrained condition.